Dynamic analysis of a novel time‐lag four‐dimensional fractional‐order financial system

In this paper, a novel four‐dimensional fractional‐order financial system (FFS) with time delay is presented. Unlike traditional bifurcation analysis of financial systems, the selection rules of two bifurcation points within the system are discussed. In addition, the motion state of the system in the vicinity of two bifurcation points are analyzed separately, such that the dynamic analysis of this novel nonlinear fourth‐dimensional FFS is more comprehensive. The detailed dynamical behaviors of this financial system, such as oscillation, stability, and bifurcation points, are deduced via rigorous mathematical analysis. Finally, some simulations are performed to verify the dynamic characteristics of the FFS around the two bifurcation points which satisfy the selection conditions of the bifurcation point.     

Fixed‐time synchronization for complex‐valued BAM neural networks with time delays

In this paper, the fixed‐time synchronization for complex‐valued bidirectional associative memory (BAM) neural networks with time delays is studied. Based on the fixed‐time stability, the Lyapunov functional method and some inequality techniques, a new criterion is presented to guarantee that the addressed systems achieve synchronization in fixed time and a more accurate estimation independent of the initial conditions is given for the settling time. Meanwhile, a new nonlinear delayed controller different from the existing ones is designed. In the end, two numerical examples are provided to illustrate the effectiveness of the obtained result.     

基于边缘敏感的SLIC和二次密度聚类的GGO分割

针对磨玻璃肺结节(Ground Glass Opacity,GGO)边界对比度低、大小各异和灰度不均匀等造成分割准确率低的问题,提出一种基于边缘敏感的SLIC和二次密度聚类相结合的分割算法。将图像边缘检测结果与SLIC超像素算法相结合,并将其中含有边缘的超像素块用区域质心代替其原始聚类中心,改善SLIC边界黏连性较差的问题;针对密度聚类不能完整分割GGO的问题,提出二次密度聚类的方法,对密度聚类定位到的簇及其邻域簇进行二次密度聚类。实验结果表明,该算法分割GGO的平均准确率达90.17%,灵敏度达84%。     

基于国产处理器增量式实时交通流预测算法及实现

针对城市交通难以处理大量数据且实时性差等问题,提出了根据增量式城市交通流数据预测拥堵情况的一种基于国产处理器的L-BFGS(limited-memory BFGS)算法。该算法通过存储向量序列计算Hessian矩阵,改进Two-Loop算法求下降方向,在Spark集群中并行处理时收敛速度快,适用于实时性要求强的城市交通场景。实验结果证明,L-BFGS预测算法完全可以在国产平台上对大规模的实时交通数据流进行快速建模、预测,在改善城市交通管理水平提供有效支撑的同时也丰富了国产芯片的应用领域。     

有限产能下多部件设备视情维修策略与多订单批量生产联合优化研究

针对有限产能下,面对多个不同要求订单时的订单选取和多部件设备维护决策问题,提出了基于客户满意度的多部件设备视情维修策略和多订单批量生产的联合优化模型。首先,基于比例风险模型描述出各部件的具体劣化趋势,并以虚拟年龄表示各部件的健康状态;其次,根据单次批量生产结束后的实时监测结果和维修阈值,确定不同的维修方式;再次,以利润最大化为优化目标,结合有限产能批量问题模型和客户满意度模型,建立视情维修策略和多订单批量生产联合优化模型;最后,利用模拟退火算法和粒子群算法就行模型求解,并通过算例验证了模型的有效性,使模型更具有现实意义,并对模型相应参数进行了灵敏度分析。     

认知任务驱动的fMRI脑功能网络构建方法

针对脑功能网络的构建受到特定大脑图谱对兴趣点描述准确度及覆盖度的限制,提出了基于认知任务信息和神经影像数据的脑功能网络构建方法。首先计算fMRI体素对于认知任务的敏感度,然后在此基础上选取兼顾分布均衡和去中心化的大脑兴趣点,从而构建任务驱动的脑功能网络。实验通过在人脸情绪识别认知任务相关的梭状回构造任务驱动的脑功能网络,其度中心性、聚类系数、全局效率、局部效率这四个复杂网络指标均优于典型大脑图谱梭状回中兴趣点构成的网络。结果表明,计算得到的大脑兴趣点具有更强的整合性,更适合用于表征特定认知任务下的脑功能网络。     

改进麻雀搜索算法求解作业车间调度问题

针对最小化完工时间的作业车间调度问题(JSP),提出改进麻雀搜索算法(ISSA).首先设计有效的编码转换方式,形成JSP离散决策空间与麻雀搜索算法(SSA)连续搜索空间的对应关系.然后,针对SSA在求解后期易陷入局部最优,利用量子计算、正余弦搜索和警戒者数量递减策略对SSA进行改进,同时引入多邻域搜索和高斯扰动策略以弥补SSA在求解离散问题时深度发掘能力不足的弊端.最后,进行FT、LA系列10个测试问题、6种算法和2个应用实例的对比实验.结果表明,ISSA在求解JSP时,能获得更好的最小值、平均值和寻优成功率,验证了ISSA求解JSP的有效性.     

基于半经典量子傅里叶变换的◢t◣-比特半经典相位估计算法实现

半经典量子傅里叶变换(quantum Fourier transform,QFT)是通过测量计算线路中特定的比特,依据测量结果经过经典信息处理控制下一个比特的变换.利用半经典量子傅里叶变换思想,提出了t-比特半经典量子相位估计算法,并在IBMQ Experience量子云平台、IBMqiskit量子模拟器和国内本源悟源云平台量子模拟器上开展了不同规模的半经典相位估计实验.实验表明,该方法提高了估计精度的同时减少了算法对线路规模和两比特受控门的依赖.     

High-Precision Position Tracking Control of Electro-hydraulic Servo Systems Based on an Improved Structure and Desired Compensation

How to improve the position tracking accuracy of electro-hydraulic servo system is a hot issue today. Full state feedback control has received widespread attention for its ability to significantly improve control performance, however, its practical application range is limited in view of the large influence of measurement noise. In terms of this issue, we propose an adaptive robust controller based on improved structure and desired compensation. Firstly, to reduce the impact of measurement noise, the actual state value is substituted by the corresponding desired value in the controller design based on model compensation and the adaptive model compensator. Then, we introduce a new auxiliary variable into the controller to optimize its structure. In addition, nonlinear robust control laws are integrated in the controller to balance unstructured uncertainties. Simulation analysis shows that the proposed control strategy not only achieves the asymptotic tracking when parameter perturbation exists, but also ensures a specified transient response and final tracing precision under the combined influence of structured and unstructured uncertainties. The results indicate that the control strategy has good control accuracy as well as strong robustness.

     

An Adaptive Fault-tolerant Control Method for Robot Manipulators

International Journal of Control, Automation and Systems - This paper presents a new method for adaptive continuous nonsingular fast terminal sliding mode control (ACNFTSMC) based on a novel...